Electrochemistry is a branch of chemistry that studies chemical reactions occurring in a solution at the interface of an electron conductor and an electrolyte. The reaction can involve electron transfer between the electron conductor and the electrolyte. For example, the electron conductor may be an electrode comprising a metal or a semiconductor.
Under some circumstances, the chemical reactions discussed above may be driven by applying either an externally derived voltage or a voltage created by the chemical reaction. Under these circumstances, these chemical reactions are known as electrochemical reactions. Moreover, some chemical reactions where electrons are transferred between one or more molecules are known as oxidation/reduction or redox reactions. Generally, electrochemistry relates to situations where oxidation and reduction reactions are separated in space or time and are connected by an external electric circuit that may be used to understand the reaction.
Some electrochemical analyses can be undertaken in a disposable cartridge that may include a reagent for inducing electrochemical reactions monitored, detected, or quantified by one or more sensors. Some conventional cartridges may be configured to operatively engage a reader device that initiates a protocol, such as via the mechanical actuation of the cartridge. Furthermore, the reader device may receive data signals that may be processed to produce test results of the reaction occurring within the cartridge.
Many conventional systems with or without cartridges use passive systems for quality control and quality assurance. For example, some systems rely on the reader device to monitor the functions within the system and quality control checks during the performance of the assays. Moreover, in some conventional systems, these checks are performed only at the beginning and the end of the performance of the assay, with little to no monitoring during the assay itself. As a result, some conventional assays are not properly monitored and stringent quality control cannot be maintained during the performance of the assays.
Moreover, at least some conventional systems do not include sensors that can monitor physical events during the performance of the assays. For example, some conventional sensors are not configured to detect physical events occurring within the system, such as fluid fronts, to enable a user and the system to monitor the progress of the assay and to ensure that the components are properly functioning and calibrated.